In a network that supports label switched paths (LSPs), such as a Generalised Multi-protocol Label Switching (GMPLS) network, label switched paths (LSPs) between nodes of the network are used to transport traffic across the network. Thus a label is applied to a packet containing traffic that has arrived at an ingress node of the label switched path before the labelled packet containing the traffic is sent to a successive node in the label switched path. At each of the successive nodes along the label switched path, the packet containing the traffic is routed according to the label applied to the packet. Typically the label switched paths in such a network may be a unidirectional label switched path (LSP) or may be a bi-directional label switched path (LSP).
In such a network supporting label switched paths it is possible to control the bandwidth allocated to a label switched path and also the quality of service (QoS) provided by a label switched path (LSP).
Currently, it is possible to specify different bandwidth allocations for the forward and return path (upstream and downstream directions) of the bidirectional label switched path (LSP). However it is not possible to specify the quality of service (QoS) to be applied to the return path of a bi-directional label switched path separately from the quality of service (QoS) specified for the forward path, for example to configure a different quality of service (QoS) for the forward and return paths of a bi-directional label switched path.
The present invention seeks at least to ameliorate disadvantages of the prior art and to provide a novel method of and apparatus for configuring quality of service (QoS) for the return path of a bi-directional label switched path.